JP2006526520A - Equipment for processing synthetic resin materials for recycling - Google Patents

Abstract

ここで、
Ｄは、円筒形柱状収容容器１の内径、又は、容量を同じくし、有効高さを同じくするように変換された仮想円筒形柱状収容容器の内径であり、
ｄは、スクリュ径であり、
Ｋは、５０よりも大又は５０に等しい定数である。Preferably, an apparatus for processing a thermoplastic, synthetic resin material for recycling has a container (1) with at least one rotating mixing and / or grinding tool (14) therein. The material to be treated is supplied through an outlet opening (17) provided at the bottom of the container (1), through which the supply opening (18) of the housing (19) is fluidly connected. In this housing, at least two screws (21, 22) are provided for delivering the material together. The diameter (D) of the container (1) and the diameter (d) of each of the screws (21, 22) have the following relationship.

here,
D is the inner diameter of the cylindrical columnar storage container 1 or the inner diameter of the virtual cylindrical columnar storage container converted to have the same capacity and the same effective height,
d is the screw diameter,
K is a constant greater than or equal to 50.

Description

  The present invention is an apparatus for processing synthetic resin materials for recycling, in particular, thermoplastic waste plastic materials, having a receiving container with an inlet opening for a material to be processed at the top, and at least one movable. A mixing and / or grinding tool is provided in the container, which preferably rotates about the longitudinal axis, and the material to be processed by this tool is an outlet provided at the bottom of the container. An opening, wherein the supply opening of the housing of the device with the screw is supplied through an outlet opening that is fluidly connected.

  An apparatus of this kind is known, for example, from EP 1173315, and the plasticizing or granulating device comprises an extrusion screw, which is the next stage, which is usually a granulating device for the material carried by the screw. Direct supply to the processing equipment. However, this screw may be a simple screw conveyor that delivers the material to the next processing step, for example, a further processing step with a rotating instrument. Only after these subsequent processing steps, the material is fed to the plasticizer or granulator. The operation of such a known device is basically satisfactory, but when feeding to a device connected to the outlet opening, in particular the device connected to the outlet opening is a plasticizing device or a granulating device. In some cases, several problems often arise. The supply to the screw should be as uniform as possible, and the delivery from the device connected to the outlet opening should be as uniform as possible. This is particularly important when a molding plant is connected to the extruder. In the case of a molding plant, what is important is that the material to be molded is delivered as uniformly as possible. The above-mentioned problem arises because, among other things, the material to be treated usually varies greatly in terms of its chemical composition and its external factors (dirt degree, particle size, grain shape, etc.).

  The object of the present invention is to eliminate these problems and to provide a device of the type mentioned at the beginning, in which the material to be treated is fed as evenly as possible to the device connected to the outlet opening, in particular at the delivery end of the screw, It is an improvement to achieve uniform delivery at the delivery end of the plasticizer or granulator.

ここで、
Ｄは、円筒形柱状収容容器の内径（単位は、ｍｍ）、又は、容量を同じくし、有効高さを同じくするように変換された仮想円筒形柱状収容容器の内径（単位は、ｍｍ）であり、
ｄは、スクリュ径（単位は、ｍｍ）であり、
Ｋは、５０よりも大又は５０に等しい定数である。 The present invention achieves this purpose by the fact that the housing of the device connected to the outlet opening comprises at least two screws into which the material from the container is fed, the diameter D of the container and the diameter d of each of the screws, Is achieved by the following relationship.

here,
D is the inner diameter (unit: mm) of the cylindrical columnar storage container, or the inner diameter (unit: mm) of the virtual cylindrical columnar storage container converted to have the same capacity and the same effective height. Yes,
d is a screw diameter (unit is mm),
K is a constant greater than or equal to 50.

  For this reason, in the configuration of the present invention, instead of the conventional single screw, the feeding is performed by a double screw or a multiple screw. In the case of a double screw extruder, it has conventionally been necessary to consider that the cost is relatively high, but from the experience of the applicant, it is necessary in a single screw configuration in order to achieve a somewhat uniform feeding operation. Complex means have been found to be comparable to the cost of a dual screw configuration. Furthermore, the screw and body in the dual screw configuration can be much shorter than in the single screw configuration, and yields of about 1.5 to 2 times can be achieved with the same screw diameter (eg, polyethylene). To process).

  However, in order to ensure the above-described uniform supply to the screw in this respect, the above-described dimensional relationship of the storage container is important.

  The configuration according to the present invention makes the supply of the material being processed to the screw constant even when the material in the container is softened by heating. The screw length is about half shorter in the case of the double screw configuration than in the case of the single screw configuration, and if the apparatus has the same yield, the space is considerably saved. Good plasticizing properties are provided in the wedge region of the screw. This is because the material to be treated is particularly strong and undergoes shearing and kneading action at this point. With regard to the shape of the screw, it has been found that the device is more versatile because the shape is not very important for processing various synthetic resins.

  Another advantage of the arrangement according to the invention is that a cooled grooved sleeve, which is conventionally required in the supply area and is subject to considerable wear, is no longer necessary. This not only saves money, but also has the advantage that the starting torque of the drive device is low.

  In the configuration of the present invention, according to experience, K is preferably a numerical value greater than 100.

  In the configuration of the present invention, the supply to the device composed of a plurality of screws and their housings is processed especially when the device composed of a plurality of screws and these housings constitutes a plasticizing device or a granulating device. It has also been found that the inner material improves as the distance from the containment vessel to the screw decreases. Therefore, according to another aspect of the present invention, the configuration of the present invention is such that the supply opening of the housing of the plasticizing device or the granulating device is directly adjacent to the outlet opening of the storage container or the outlet opening of the storage container To be matched. For this reason, the housings of the two screws are preferably connected tangentially to the circumference of the container, but different arrangements, for example radial arrangements, are also possible in principle.

  In the configuration of the present invention, the most preferable arrangement is that the screws in the housing of the plasticizing device or granulating device are located in a vertical or diagonal manner with one side up in the region of the supply opening in the cross section. Is the case. By adopting the vertical arrangement, the path of the material to be processed from the container to the screw is minimized. As a modified form of this arrangement, in the cross section, the screws may be arranged obliquely or in a parallel arrangement, but in the modified form, in order to prevent the deposited material from adhering to the surface. In the region of the feed opening, it is usually necessary to cool the corresponding surface in the housing of the plasticizer or granulator and thus to provide a plurality of cooling ducts.

  The screw threads of the plurality of screws may engage with each other at least in the region of the supply opening. This has the advantage of providing a self-cleaning action of the screw thread, which is particularly important in the supply area. The two screws preferably have the same diameter, but this is not absolutely necessary and the two screws are, for example, one screw serving as a supply screw for the other screw. When functioning, the lengths may be different. When the screw diameters are different, the average value of the screw diameters is defined as d in the above formula. When the screw diameter is not constant in the length direction of the screw (for example, in the case of a conical screw), the average diameter of the screw is used.

The advantageous supply action of the material to be treated, mentioned at the outset, is that in the arrangement according to the invention, the side wall of the supply opening, which the device discharges, constitutes an enlargement of the supply opening, Projecting in the direction of the longitudinal axis of the screw housing without interruption, in the direction of the axial axis of the plurality of screw housings, at least, preferably in the region of the axial line of the screw, up to the periphery of the adjacent screw thread This enlargement is further improved by constructing a continuous cutting edge that cooperates with the thread. In a particularly preferred embodiment, the side walls constituting the enlarged portion of the supply opening make an angle of 20 to 80 degrees, preferably 30 to 55 degrees with respect to the axis of the screw. According to experiments, it has also been found that the following relational expression applies particularly to the supply opening of the screw housing:

h ≧ k0.6d and
L ≧ k0.6d

here,
h is the effective height (unit is mm) of the supply opening measured in the axial direction of the container;
L is the effective length (unit is mm) of the supply opening, measured in the circumferential direction of the container,
d is the outer diameter of the screw thread (unit is mm);
k is the number of screws, and k is 1 or 2.

  Furthermore, it is preferable that the base of the supply opening is a downward slope from the screw toward the storage container.

  Other features and advantages of the present invention will become apparent from the description of the embodiments of the present invention schematically shown in the accompanying drawings.

  In the apparatus shown in FIGS. 1, 2, 6 and 7, this apparatus constitutes a crushing / extrusion combined apparatus having a double screw, and includes a container 1 having a longitudinal axis 2 and having a circular cross section. The side wall 3 of the container projects substantially cylindrically. The support plate 4 rotates around the axis 2 in the direction of the arrow 8 (FIG. 2) in the container 1 and rests on the shaft 5. The shaft penetrates the bottom 6 of the container 1 in a sealed state. It protrudes and is rotatably attached to the bottom 6 within the plurality of bearings 7.

  An inlet opening 10 for the material to be processed is provided at the top of the container 1, and this inlet opening is preferably a funnel-shaped covering wall 11. When the material to be processed is to be processed in a vacuum state, a suction device is connected to the container 1 and a gate valve is attached to the inlet opening 10 so that the material can be exhausted satisfactorily. The material to be treated is supplied to the inlet opening 10 by a feeder 12 such as a belt conveyor, and dropped into the inlet opening 10 in the direction of the arrow 13.

  The support plate 4 provided in the region of the bottom 6 supports a plurality of instruments 14, which are at least mixed with the material to be treated introduced into the container 1, usually a recycling thermoplastic material. In addition, the synthetic resin material to be treated is usually pulverized and dried. In the latter case, the instrument 14 has a cutter shape with a blade. The treated synthetic resin material that is rotated away from the tool 14 of the support plate 4 becomes the mixing vortex 15 and ascends the side wall 3 of the container 1 and reaches the highest point 16, and then reaches the region of the axis 2 of the container. Fall into. In this way, the material to be treated is thoroughly mixed or pulverized and dried, and is discharged from the storage container through the outlet opening 17 after an appropriate residence time in the storage container 1 has elapsed. This outlet opening coincides with the supply opening 18 of the housing 19 of the plasticizing or granulating device (in the case of the extruder) 20 in the illustrated embodiment, but the outlet opening is in the supply opening 18. At least fluidly connected. The plasticizing or granulating device 20 comprises two screws 21 and 22 which are provided in the housing 19 and are driven in the same rotational direction by a drive device 23 so that their threads engage each other. It is rotated synchronously. Examples of drive systems suitable for such rotation are shown in FIGS. The drive 23 drives a sun gear 24 mounted in a transmission housing 25, which is fixedly connected to the shafts of the two screws 21 and 22 for two satellites. The gears 26 and 27 are driven.

ここで、Ｄは、収容容器１の内径（単位は、ｍｍ）であり、ｄは、２本のスクリュ２１及び２２のねじ山の外径（単位は、ｍｍ）であり、Ｋは、少なくとも５０、好ましくは、少なくとも１００である定数である。この関係式は、円筒形柱状収容容器に当てはまる。この収容容器が、円筒形でない、又は円錐形等の非円筒形である場合には、例えば、Ｄは、容量を同じくする、すなわち、有効高さを同じくする仮想円筒形柱状収容容器の内径に変換する必要がある。有効高さＨは、動作条件が、適切であれば、支持板４の上端の上方での、混合渦１５の最高点１６の距離とみなす。 In order to double the yield as compared with a single screw extruder, it has been found that the dimensions of the container need to satisfy the relationship according to the experimental side obtained by the experiment shown below.

Here, D is the inner diameter (unit is mm) of the container 1, d is the outer diameter (unit is mm) of the threads of the two screws 21 and 22, and K is at least 50 , Preferably a constant that is at least 100. This relational expression applies to a cylindrical columnar container. When this container is not cylindrical or non-cylindrical, such as conical, for example, D is equal to the inner diameter of the virtual cylindrical columnar container having the same capacity, that is, the same effective height. Need to convert. The effective height H is regarded as the distance of the highest point 16 of the mixing vortex 15 above the upper end of the support plate 4 if the operating conditions are appropriate.

However, in many cases, the size and shape of the supply opening 18 of the screw housing 19 is also important. The synthetic resin material, which is mixed in the container 1, preferably pulverized and heated, and more preferably dried, is introduced into the supply opening by a plurality of instruments 14. The supply opening is at least partially located at the height of the plurality of instruments 14 that rotate within the container 1. Such an effect is that the tips of the plurality of instruments are angled or curved with respect to the moving direction in the direction of the arrow indicated by reference numeral 8, and the synthetic resin material is pushed into the supply opening 18 with a spatula shape. Operation is also facilitated by having it occur during rotation of the plurality of instruments 14. According to a plurality of experiments, it was found that the following relational expression is particularly preferable when the supply opening 18 is applied.

h ≧ k0.6d and
L ≧ k0.6d

here,
h is an effective height (unit: mm) of the supply opening 18 measured in the axial direction of the container 1;
L is an effective length (unit is mm) of the supply opening 18 measured in the circumferential direction of the container 1.
d is the outer diameter of the screw thread (unit is mm);
k is the number of screws, and k is 1 or 2.

  The effective clear cross-section regarding the moving direction of the synthetic resin material from the container 1 to the housing 9 is regarded as the effective length or effective height of the supply opening 18.

  Further, according to a plurality of experiments, the synthetic resin material introduced into the supply opening 18 is discharged from the plurality of instruments 14 at the end of the supply opening 18, that is, the region at the left end of the supply opening 18 in FIG. 2. From time to time, it has been found that there is a tendency to accumulate. In order to avoid this accumulation, the side wall 28 of the supply opening 18 (this is the side wall 28 on the right side in FIGS. 3 and 4) from which the plurality of instruments 14 are discharged is referred to in the longitudinal direction of the screw housing 19. It has been found that it is preferable to provide it obliquely with respect to the axis 29 so that the enlarged portion 36 of the supply opening 18 continuously expands toward the axis of the screw in the supply direction of the synthetic resin material. The angle α (FIG. 7) formed by the side wall 28 with the longitudinal axis 29 of the screw housing 19 is less than 90 degrees, preferably 20 degrees to 80 degrees, and more preferably 30 degrees to 30 degrees. It is 55 degrees. This side wall 28 projects at least as far as the periphery of the thread 30 of the adjacent screw 21 or 22, preferably towards the region of the axis of this screw. When the two screws 21 and 22 are arranged vertically, the longitudinal axis of the screw coincides with the axis 29 of the screw housing 9 when viewed in plan (FIG. 2). The end of the side wall 28, in particular its tip, constitutes the cutting edge 39 (FIGS. 1, 5 and 6), cooperates with the screw thread 30 and is not provided with a grooved sleeve, It protrudes in the circumferential direction of 22 continuously, that is, without interruption.

  In the embodiment shown in FIGS. 1, 2 and 7, the two screws 21 and 22 are arranged one above the other, and the axes of these screws extend horizontally. Although it is most preferred that the two screws are in a vertical configuration, it is not absolutely necessary. As a modification of such arrangement, the two screws 21 and 22 may be arranged side by side in the horizontal direction as shown in FIGS. In the embodiment shown in FIG. 3, the two screws are equal in length and are rotated in the same direction, and both screw threads 30 engage each other. For this reason, the two screws 21 and 22 are fed together with the extruder head 31 connected to the screw housing 19.

  The arrangement shown in FIG. 4 is different from the arrangement shown in FIG. 3 in that the two screws 21 and 22 have different lengths, that is, the screw 21 adjacent to the container 1 is shorter than the other screw 22. It is different. For this reason, the screw 21 receives the synthetic resin material charged from the container 1 through the outlet opening 17 and takes it into the supply opening 18 of the screw housing 19. This supply operation can be improved by making the container 1 and the supply opening 18 have the above-described dimensional relationship and further providing the side wall 28 of the supply opening. During the feeding operation, the screw 21 passes the received synthetic resin material to the other screw 22, and the other screw sends the synthetic resin material to the connected extruder head 31. In addition to the effect of uniform delivery, this arrangement has the effect of lowering the price of the delivery housing 37 and lowering the price of the inlet member leading to the extruder head 31.

  FIG. 6 shows details of the shape of the supply opening 18 for placement shown in FIGS.

  As can be seen from FIGS. 5, 6 and 7, an additional chamfer 32 is provided at the end of the supply opening 18 from which the plurality of instruments 14 discharges, i.e., at the right end in FIGS. Improve supply operation. Further, the base portion 33 of the supply opening 18 is inclined toward the storage container 1 so that the wall of the supply opening (a wall formed by the base portion 33) is a descending slope toward the storage container 1 from the screw 22.

  As described above, the two screws 21 and 22 may take any positional relationship with each other in principle. Various arrangements are shown in FIGS. As shown in FIG. 11, the most preferable arrangement is that the two screws 21 and 22 are arranged vertically. This is because, in this case, unlike the other arrangements of the two screws 21 and 22, there is no possibility that the synthetic resin particles adhere to the surface of the supply region of the screw housing. An arrangement different from the arrangement shown in FIG. 11 is possible in principle. However, in the arrangement different from the arrangement shown in FIG. 11, the above-described adhesion of the adhesive synthetic resin particles and the accompanying blocking of the supply opening are performed. Can happen. In the case of an arrangement different from the arrangement shown in FIG. 11, the supply opening is an area of the housing 19 where the supply opening 19 is formed, and a plurality of hollow portions 35 are provided in the vicinity of the supply opening 18. Because of the presence of these cavities 35, the above-described adhesion occurs, and as a result, a plurality of cooling ducts 34 are provided in a region where the treated synthetic resin particles are exposed to an excessively long residence time. Is preferred. The larger these cavities 35 are, and the more these cavities protrude from the container 1 into the housing 19, it is necessary to provide more cooling ducts 34.

  It is most preferable in terms of cost that the two screws 21 and 22 have an equal and constant screw thread d (FIG. 7), but this shape is not absolutely necessary. FIG. 15 shows an embodiment in which two screws 21 and 22 are both formed into a conical shape and are fed together to the head 31 of the extruder to constitute a double screw extruder. The two screws 21 and 22 are driven in opposite directions by a common driving device 23 via gears 38 that mesh with each other. In this embodiment, the screw threads 30 can mesh with each other and also provide a self-cleaning action in the supply area.

  A horizontal arrangement of the housing 19 with the screws 21 and 22 is most preferred, but such a housing is connected to the receiving container 1 with an inclined longitudinal axis, and if necessary connected vertically. Is also possible.

  In the above-described embodiments, only two screws are shown, but it is theoretically possible to provide three or more screws with the same configuration. The relational expression described above is also applied to such an aspect. However, the aspect of providing three or more screws is not very important for economic reasons.

FIG. 1 is a longitudinal sectional view taken along line II of FIG. 2 in the first embodiment. FIG. 2 shows a cross-sectional view taken along line II-II in FIG. FIG. 3 shows a horizontal cut-away view of an embodiment of screws of equal length arranged in parallel. It is a modification of embodiment shown in FIG. 3, Comprising: The aspect from which the length of two screws differs is shown. FIG. 5 shows the formation portion of the supply opening in the embodiment shown in FIG. FIG. 6 shows the formation portion of the supply opening in the embodiment shown in FIG. FIG. 7 shows the forming portion of the supply opening in a horizontal sectional view. FIG. 8 shows an exemplary longitudinal section of a screw arrangement. FIG. 9 shows an exemplary longitudinal section of a screw arrangement. FIG. 10 shows an exemplary longitudinal section of a screw arrangement. FIG. 11 shows an exemplary longitudinal section of a screw arrangement. FIG. 12 shows an exemplary longitudinal section of a screw arrangement. FIG. 13 shows an exemplary longitudinal section of a screw arrangement. FIG. 14 shows an exemplary longitudinal section of a screw arrangement. FIG. 15 is a horizontal cross-sectional view of an embodiment of a conical double screw.

Claims (11)

A device for processing synthetic resin materials for recycling, in particular thermoplastic waste plastic materials, having a receiving container (1) with an inlet opening (10) for the material to be processed at the top, and at least one movable A free mixing and / or grinding tool (14) is provided in the container (1), preferably rotated about the longitudinal axis (2) of the container and processed by this tool (14). The material to be treated is an outlet opening (17) provided at the bottom of the container (1) and is supplied to the housing of the device (20), preferably a plasticizing device or granulating device, comprising a screw (21). In an apparatus in which the opening (18) is fed through an outlet opening that is fluidly connected, the apparatus (20) connected to the outlet opening (17) is fed together with material from the containment vessel (1). at least With this screw (21, 22), and each of the diameters of the container (1) (D) and screw (21, 22) (d), the device characterized in that a relation below.

here,
D is the inner diameter (unit is mm) of the cylindrical columnar storage container (1) or the inner diameter of the virtual cylindrical columnar storage container converted to have the same capacity and the same effective height (unit: mm),
d is a screw diameter (unit is mm),
K is a constant greater than or equal to 50.   Device according to claim 1, characterized in that K is greater than 100.   The housing of the device (20) for accommodating the screws (21, 22) is directly connected to the outlet opening (17) of the receiving container (1), and the supply opening (in the housing (19) of the device (20) ( 18) according to claim 1 or 2, characterized in that 18) is directly adjacent to the outlet opening (17) of the receiving container (1) or coincides with the outlet opening (17) of the receiving container (1). The device described.   Device according to claim 3, characterized in that the housing (19) of the two screws (21, 22) is connected tangentially to the circumference of the receiving container (1).   The screws (21, 22) in the housing (19), when viewed in cross section, are positioned vertically or diagonally with one of them facing up in the region of the supply opening (18). The apparatus of claim 4.   Device according to claim 5, characterized in that in the region of the supply opening (18), a plurality of cooling ducts (34) are provided in the housing (19) of the screw (21, 22).   7. A device according to any one of the preceding claims, characterized in that the threads (30) of the screws (21, 22) mesh with each other at least in the region of the supply opening (18).   The side wall (28) of the supply opening (18) discharged by the instrument (14) constitutes an enlarged portion (36) of the supply opening (18), and the enlarged portion (36) comprises the screw (21, 22) projecting without interruption in the direction of the longitudinal axis (29) of the housing (19) and in the direction of this longitudinal axis, around the thread (30) of the adjacent screw (21 or 22) Characterized in that the enlarged portion (36) constitutes a continuous cutting edge (39) cooperating with the screw thread (30), at least projecting to the region of the axis of the screw. The apparatus according to any one of 4 to 7.   The side wall (28) constituting the enlarged portion (36) of the supply opening (18) is 20 degrees to 80 degrees, preferably 30 degrees with respect to the longitudinal axis (29) of the screw housing (19). 9. The device according to claim 8, characterized in that it makes an angle of from 55 to 55 degrees. Device according to any one of the preceding claims, characterized in that the following relational expression applies to the supply opening (18) of the housing (19) of the screw (21, 22):

h ≧ k0.6d and
L ≧ k0.6d

here,
h is the effective height (unit is mm) of the supply opening (18) measured in the axial direction of the container (1);
L is the effective length (unit is mm) of the supply opening (18) measured in the circumferential direction of the container (1),
d is the outer diameter (unit is mm) of the screw thread (30) of the screw;
k is the number of screws, and k is 1 or 2.   The base (33) of the supply opening (18) is a descending slope from the screw (21, 22) toward the receiving container (1), according to any one of the preceding claims. Equipment.

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